11 78 540 Replacing left monitor sensor (N63)

Special tools required: 

• 11 7 020

Only perform this work after engine has cooled down.

Necessary preliminary work 

• Check function of DME control unit.
• Switch off ignition.
• Remove AIR FILTER HOUSING .

Release retaining clip (1).

Remove heat shield wire ring (2) over oxygen sensor.

Detach oxygen sensor cable from retaining clips (3).

Fig 1: Identifying Heat Shield Wire Ring And Retaining Clips

Courtesy of BMW OF NORTH AMERICA, INC.

Release monitoring sensor (1) with special tool 11 7 020 .

Fig 2: Releasing/Tightening Monitoring Sensor Using Special Tool (11 7 020)

Courtesy of BMW OF NORTH AMERICA, INC.

Installation note: 

The threads of new lambda control/monitoring sensors are already coated with Never Seez Compound (refer to BMW Parts Department).

If a lambda control/monitoring sensor is to be reused, apply a thin and even coating of Never Seez Compound to the thread only.

The part of the lambda control/monitoring sensor which projects into the exhaust branch (sensor ceramics) must not  be cleaned and not  coated with lubricant.

Fasten monitoring sensor (1) with special tool 11 7 020 .

Tightening torque 11 78 1AZ .

Fig 3: Releasing/Tightening Monitoring Sensor Using Special Tool (11 7 020)

Courtesy of BMW OF NORTH AMERICA, INC.

Installation note: 

Check function of DME control unit.

Pay attention to cable routing of monitor sensor.